Round, round, get around, I get around

Electrons are really, really, really round, according to research conducted by Imperial College scientists. The research, which was published in the journal Nature and took over ten years to complete, found that the electron differs from being perfectly round by less than 0.000000000000000000000000001 cm. This means that if the electron was magnified to the size of the solar system, it would still appear spherical to within the width of a human hair. Using a very precise laser, the researchers made careful measurements of the motion of electrons. If the electrons were not perfectly round then, like an unbalanced spinning-top, their motion would exhibit a distinctive wobble, distorting the overall shape of the molecule. The researchers saw no sign of such a wobble.

Research co-author, Dr Jony Hudson, from the Imperial College Physics Department, said: “We’re really pleased that we’ve been able to improve our knowledge of one of the basic building blocks of matter. It’s been a very difficult measurement to make, but this knowledge will let us improve our theories of fundamental physics. People are often surprised to hear that our theories of physics aren’t ‘finished’, but in truth they get constantly refined and improve by making ever more accurate measurements like this one.”

The researchers are now planning to measure the electron’s shape even more closely. The results of this work could have major implications for the study of antimatter, an elusive substance that behaves in the same way as ordinary matter, except that it has an opposite electrical charge. For example, the antimatter version of the negatively charge electron is the positively charged anti-electron (also known as a positron). Understanding the shape of the electron could help researcher understand how positrons behave and how antimatter and matter might differ from one another.